rc2: macOS cross-compile fix + security/recovery hardening

- build.rs: pass target -arch to cc so macos_shim cross-compiles (x86_64-apple-darwin)
- AACS/CSS: unit-aligned decrypting sweep; per-VTS CSS title keys (hard-fail on wrong VTS);
  reject truncated Unit_Key_RO; AACS 2.0 sig-verify skip; CSS bus-auth random nonce
- recovery: gap-filling mapfile load; sweep/copy resume reconciliation; stale-mapfile abort;
  patch wedge/damage-window range reset
- mux: TS continuity + PSI CC desync guards; HEVC numTemporalLayers clamp; MPEG-2 pending
  byte-cap; PS parse_pts marker-bit validation; HdrFormat strict parse; Unknown-variant metadata
- net/keydb: network:// SSRF parity (IPv4-mapped, CGNAT, 0.0.0.0/8, Class-E); bounded keydb
  header read + size cap + error context
- io: durable mapfile fsync; NFS writeback degrade; sync_file_range error capture;
  Windows SCSI u32 transfer guard

tests/crypto_tests.rs

@@ -16,6 +16,7 @@ use libfreemkv::css;
 fn css_descramble_sector_roundtrip_via_public_api() {
     let state = css::CssState {
         title_key: [0x42, 0x13, 0x37, 0xBE, 0xEF],
+        crack_span: None,
     };
 
     let mut sector = vec![0xAAu8; 2048];